1、 Main advantages
1. Save energy and reduce operating cost.
2. Extension Roots blower Service life.
3. Soft start and no large current impact.
4. Improve power factor and reduce reactive power loss.
5. It has the function of automatic energy-saving control, and can automatically adjust the voltage according to the load condition, so that the motor can run in the highest efficiency state.
6. The frequency converter adopts low frequency output rated torque, which can Roots blower Implement strong control.
2、 Selection of frequency converter
1. To select ordinary frequency converter, the capacity needs to be enlarged by 1-2 grades. For example, for 75kW fan, 90kw or even 110KW inverter can be selected
2. Select frequency converters that support constant torque, such as Siemens MM440, Schneider atv71, abb ACS550 or above, etc.
In addition, in order to reduce Roots blower The starting current must be vented. (vent the pipeline during startup, and close the vent valve after startup).
In addition, the control cabinet should be purchased from the blower manufacturer, Roots blower The control cabinet is different from the inverter of centrifugal fan and pump. Fan pump type inverter belt Roots blower When the pipeline is started under pressure, it may fail to start. Not recommended
3、 Causes of abnormal noise during operation
1. The serious overload of the fan causes the shaft deformation, which makes the impellers collide with each other and produce abnormal noise. The solution to overload is to adjust the impeller clearance.
2、 Roots blower Overload and overheating make the impeller and casing deform, resulting in friction between the impeller and the casing and produce abnormal noise. The solution is to check the filter, outlet back pressure and system pressure to reduce overload and overheating, and increase the clearance at the inlet side of the casing if necessary.
3. The belt tension is too tight or too loose, so that the fan speed is unstable, sometimes fast or slow, the gear will emit a howling sound. The solution is to adjust the belt tension properly.
4. Loose base bolts and loose connections may also cause noise from the fan. The solution is to strengthen the bolts.
The impeller is jammed by foreign matters and the impeller is out of balance due to abnormal noise and 5. The solution is to remove foreign matter.
6. When the bearing is worn and its clearance increases to more than the specified value, the two shafts supported by the bearing will vibrate and make abnormal sound. When the vibration is transmitted to the impeller, the clearance between the impellers may be damaged and the impellers collide with each other, resulting in greater abnormal noise. The solution is to replace the bearing.
7. Wear of the gear or loose fixation of the gear may make the gear itself emit abnormal noise, and damage the clearance of the impeller and the synchronization of the impeller rotation, resulting in more abnormal noise caused by the collision between the two impellers. The solution is to replace the gears.
8、 Roots blower The noise increases with the increase of boost voltage. When the pressure fluctuation is large, the noise will also fluctuate, forming a different sound than usual. The abnormal noise can be reduced by checking the pipeline and load, eliminating the blockage and ensuring that the pressure rise is stable at the specified value.
9. When Roots blower When the safety valve is opened, a sharp exhaust noise will be generated at the safety valve, and when the safety valve is repeatedly opened and closed, an abnormal sound will be formed. The solution is to check whether the fan is overpressured or adjust the safety valve - the fan is seriously overpressured and the safety valve is opened. After the pressure drops, the safety valve is closed, but it is overpressured again and again. In this way, the safety valve opens and closes repeatedly.